The present invention concerns a device for the protected output of electronically transmitted and stored documents provided with electronic copy protection, and a corresponding output method, in particular a method of operating the device. The present invention concerns in particular protection for electronic documents on a computer system, which is still operative even when a copy protection mechanism provided for the document has been switched off or overridden.
The state of the art discloses numerous devices and methods for the electronic publication of documents, in which respect the term electronic documents in accordance with the present invention is used to denote not just texts and images but also data banks, audio media, videos, animations, interactive films, control programs, active and passive computer programs and the like usable arrangements of electronic data. In this respect documents which are valuable in terms of copyright are often available in a form in which they are protected from copying, either by virtue of suitable encoding or encrypting methods, by virtue of special (proprietary) formats for a data file, characterising and/or individualizing recognition features or by suitably set, secret software interfaces. There are also solutions in existence, which for decoding purposes supply necessary data or items of information externally, for example by way of a data communication network.
All solutions of that kind however suffer from the disadvantage that, as soon as the copy protection or use protection has been circumvented by a suitable measure, an electronic document can be at any time locally manipulated and in particular also can be passed on as desired and in unlimited fashion. More specifically, due to the digital character of the documents, any copying procedures can be implemented without a loss of quality, so that after copy protection has been successfully removed, there is then anxe2x80x94illegalxe2x80x94copy which in terms of quality does not suffer from any detriment in relation to the original.
The state of the art hitherto does not offer any measures which can be used when copy protection is overridden in order to move an end user towards use of the original, in a technically supportive fashion, when the situation involves making a decision between an original and an illegal digital copy which can be unlimitedly used.
The state of the art discloses copy protection methods in which a password or a key must be supplied as additional data by way of the network. The disadvantage of these methods is that only a very limited number of barriers has to be overcome in order to put the document into a condition in which access without online authorization appears possible. The nature and the structure of the additional data which must be used for enablement purposes with that method are already very substantially established upon generation of the document or prior to the moment in time of enablement. The additionally supplied data in addition do not include any benefit or value which can be viewed independently of the enablement procedure. Delivery of the data is implemented only for reasons which are related to direct security and not for reasons which are linked to an improvement in the use or value of an electronic document.
In particular in relation to electronic documents which involve a considerable value for the authorized creator thereof, successful overriding of the copy protection therefore means that the right and the option for the author to effectively assert his property rights in respect of the document are limited or even rendered impossible.
These problems are made more severe by virtue of the fact that there are numerous service or auxiliary programs for computer systems, the purpose of which is to overcome copy protection on an electronic document and the effectiveness of which, with the present copy protection mechanisms, is continuously increasing.
Therefore the object of the present invention is to protect electronically transmitted and stored documents even when a copy protection mechanism in respect of such documents has been removed or overridden, wherein xe2x80x9cprotectionxe2x80x9d in accordance with the present invention is used to denote any difficulty or any impairment in terms of options of use in respect of an illegally copied document in relation to an original (or a legal, authorized copy). The invention also seeks to provide a corresponding method.
That object is attained by the device having the features of claim 1 and the method having the features of claim 6.
Advantageous developments of the invention are set forth in the appendant claims.
Advantageously, in accordance with the present invention, use is made of the fundamental principle of embedding the electronic document to be protected in a system environment which offers the additional operation and/or the additional data, wherein the additional value or gain to be achieved thereby can be implemented by the action of the interrogation and checking unit only when the copy protection has not been violated or overridden. A prerequisite in that respect is that the copy protection used is of such a kind that overriding or violation thereof can be detected by suitable criteriaxe2x80x94for example within the document or within software environment interfaces which are to be usedxe2x80x94by means of the interrogation and checking unit.
In addition, in accordance with the invention, advantageously at least one online contact is used by way of data communication network (xe2x80x9csessionxe2x80x9d) in order to produce the additional data or to permit the additional operation to be implemented. In that way the generation of the additional use value or information value for the (authorized) user is possible, in a particularly secure and flexible fashion.
In accordance with the above-indicated definition, electronic document files which can acquire an additional value by additional data which in particular are only present externally are suitable for the invention, as electronically transmitted and stored documents in accordance with the present invention, in which respect the electronic documents embraced by the invention are to be separably joined to that additional value. In that case the additional operations in accordance with the invention concern in particular data processing and operating procedures which produce that additional value.
In a corresponding fashion, additional operations in accordance with the invention are procedures on a computer system which can be implemented with, on and/or together with the document, and give an advantage over the original document, and which are not present without those procedures on the computer system. In specific terms, additional operations of that kind can involve the provision of an online access for a (selective) update of the document, management of key words and notes, a representation of additional management data, storage and/or representation of reading marks or bookmarks, an additional storage/representation of color marking of text passages, implemented by the user, an additional access interface for searches in associated or superior archives, the use of further services such as electronic document exchange with relevant authors or publishing houses and the use of an electronic blackboard provided for the document. In that respect the items of additional information can have been acquired as rights in respect of use (use rights) at no cost in connection with registration of the electronic document. Those additional values and data can equally well be marked separately and independently and billed by way of a billing unit. In accordance with the invention in particular the following measures are also preferred examples in respect of additional operations or additional data.
The data management envisaged can also be for example the management of rights in respect of use on documents or parts of documents which have been paid for or otherwise acquired by the end user. In that way repeated use can be selectively offered to the user without payment.
In addition an overview about the various document versions or editions or update stages can be outputted on the client computer in respect of selected document by the server management unit.
In addition a characterisation of the changes between any two or more versions can be outputted as additional value.
The output of further document titles which are in the circle of themes of the document to be protected can also be an additional value. The same category also includes the output of a passage or a list of passages from the document to be protected, which after interrogation of one of the various retrieval systems best meets the reading intention of the user.
A further value can lie in the output of a translation or a translation aid by the server management unit. That can involve for example the subtitles for a film, which are not part of the film. Alternatively, there can be current aids for the translation of given passages from a document, which occur when using a document. That can also include visual and/or parallel output of a music text and/or the associated translation.
A further additional value can lie in the deliberately interrogated output or standard output of user statistics which can be applied with the electronic document or produced therewith. That value can give the user indirect orientation about the quality of the document or a passage. The output could then include for example the frequency of duplicate use of certain passages, an overview or ranking in relation to the most frequently used passages or the frequency of use of comparable documents.
Further protection by management can also provide outputting the names of the persons who have already acquired knowledge of the document. Besides the additional information for the direct user, an additional value can also be produced or acquired, for any one or more further parties, insofar as they are permitted access to the document or selected services which can be associated with that document.
A further additional value can provide that data can be entered in a document, for example as a form, at predetermined positions, by a client user, manually or under the control of a script, which data are finally linked on the server side to specific actions. Integrity of the document, that is to say protection from change, is afforded by the specific use value. Copy protection can thus also be interpreted in each case as protection from improper change in the document.
It is not out of the question that the copy-protected document can be outputted on the computer system both in its (original) format and also in a modified format (with overridden copy protection); in the case of removal of copy protection however the user suffers a detriment in terms of value. (In general terms, in accordance with the present invention, a copy protection method in the broad sense is understood to mean not only any way which is suitable for preventing an unauthorized copy of an electronic document or making such a copy more difficult, but also a method which contributes to a reduction in quality of a copy; in the case of case of electronic documents this can be effected for example by a picture screen content, for example with an illustrated text, being copied as such and disseminated. For the subsequent discussion a correspondingly manipulated document with overridden copy protection is referred to as xe2x80x9ccrackedxe2x80x9d).
In addition copy protection is to be interpreted not only as protection from illegal production of a copy of the original, but as monitoring on the part of the publisher to prevent use of a copy in the intended sense or to make such use difficult, that is to say in the sense of protection from use.
A protection from use can also provide that a copy recognises that it is being used in an altered context and that fresh billing can arise therefrom, with the aim that it finally requires renewed enablement for use of the document.
Even if therefore the cracked document can be read or used within an editor, a viewing unit or viewer or a data bank, it is however not possible in accordance with the invention to use the additional value in the form of the additional operations and/or the additional data. Accordingly in accordance with the invention the disadvantage of the illegal copies lies in the absence of those additional value options.
The additional values of the document consist of the additional options which can arise within a suitable computer program by virtue of the addition of one or more further features and/or items of information or one or more further functions or operations which can occur outside the locally concluded database and/or the locally concluded functional extent of the electronic document.
A contact which is to be interpreted as being online in accordance with the present invention is one which claims digital information or digital services outside the local computer system by way of the data communication network. While the Internet is for example preferred for that purpose, the subsequent supply of additional items of information can also be implemented by way of another physical channel than by way of the bidirectional Internet. The additional data can also be transported to the client, after registration or verification dialogue, on a uni-directional communication medium (broadcast, satellite, uni-directional wide-band cable).
A software environment comprises operating system instructions or operations which are afforded within a computer program as interfaces.
A software environment can be identified as secure if the complication and expenditure in respect of time or material for finding a clever combination of commands within the software environment is too great that, from economic points of view, the use of the cracked document would be worthwhile for a hacker and/or for the user.
The integration of an electronic document into a software environment means that there is the possibility of the operations and instructions presented from the software environment being meaningfully applied to the electronic document. Integration can also be conversion which is implemented in accordance with fixed rules or in accordance with an algorithm and the output product of which can then be used.
The term right in respect of use is used to denote the right of a user to use a document in an established framework. That right in respect of use can be limited in terms of time or space. A right in respect of use in particular does not imply any right of transmission to a third party.
In a corresponding fashion the processing and control unit according to the invention permits both passive management of the electronic documents in which data and relationships are stored in a structured, object-oriented or relational manner. The processing and control unit can also be implemented in the form of a software environment into which optionally local services or programs can be integrated or by which services can be taken or accepted from an external server by means of remote data transmission by way of the data communication network. In addition the processing and control unit permits active management, for example by the user-guided input of notes to a document; in addition updating of the managed documents can be viewed as active management of that kind. (In that respect for example a communication from an external server that a change to the document has been made or a further comment has been posted to a public blackboard in relation to the document is viewed as an active management procedure, controlled by the processing and control unit).
A proprietary document format can have encryption to protect it from unauthorized use of the content. A document can be considered either as passive software or as an active program, in regard to which meaningful use is possible only by the provision of the associated software interfaces of a software environment.
Integration of the electronic document, in the above-described manner, into the management unit afforded by the local processing and control unit, can be made possible in that respect by an online procedure, but alternatively it can also be effected locally.
Protection by management involves the exclusion of illegal copies. Protection by management affords a second barrier in regard to protection in respect of use, which becomes operative automatically when the illegal copy or the original is used by an unauthorized user. Registration of the document must precede, to characterise illegal use. In that sense, the method described in this invention, from the point of view of the user of the document, offers only limited use in relation to unregistered use.
In a particularly preferred feature there is provided an additional input interface which as a reaction to an enablement signal from the interrogation and checking unit makes it possible to introduce or implement an electronic communication, in particular by way of the data communication network, with an author of the electronic document, who is identified as additional information. In that way, suitable and appropriate processing is supported precisely in relation to dynamic documents which are subject to development and/or a (for example scientific) dialog. That also affords completely new and efficient ways of carrying out scientific operations.
Limitation of use in respect of time cannot be implemented on a local computer which is under the total control of an outsider as the system time on the computer can be changed over at any time. Protection by management would mean in contrast that a user, in a passive sense, cannot have the certainty that his hacked document is still current, or whether further relevant items of information are not still missing. The external server which must be addressed in the context of security by management cannot be deceived by that manipulation. In an active sense however the use of the other managed documents can also be limited, after local manipulation.
With protection by management, with an illegal change to a user status of a managed document, the normal use of other documents inter alia can also be altered or only partially altered but limited in such a way as to cause problems, as long as this unintended change in status persists. The integrating and combining character of management affords the possibility, due to the risk of loss or violation of individual rights in respect of use, out of the quantity of all other documents, of obtaining protection for an individual document, transferred from the entirety. The communication that the situation involves a temporary and/or conditioned change in the use status, can be given to the user with the intention of causing the user to restore the intended and entitled status of the previously altered document or possibly erase the illegal copy.
In a preferred fashion, local installation and introduction of the documents in the management program should be effected only together with payment and/or online registration and/or upon first use. Subsequent installation and introduction of the document into the management program can be effected only when proof of payment or proof in respect of reliable enablement can be securely provided. A subsequently installed and possibly unpaid document should be reliably distinguishable from a correctly installed document. An additional billing module can provide for subsequent payment and registration. An authorized user can be distinguished from an unauthorized user only when a suitable identification module or authentication module permits a distinction to be drawn between users and thus attributes the rights in respect of use and therewith also the option of use only to be authorized users.
In a further advantageous feature registration of a relevant document takes place in a local and/or external registration unit; the action of that registration unit provides for permanent, checkable embedding of the electronic document in the system environment for use of the additional operations and/or the additional data. In particular it is then possible for the local processing and control unit, by interrogation of the external or local registration unit, to check the authenticity status of a document, without (renewed) checking of the actual document, in respect of copy protection, having to be necessary. In particular registration can also be effected in an anonymous mannerxe2x80x94without specific identification of a user.
In a further preferred feature it is also provided that the online contact according to the invention between the processing and control unit and the external data processing installation is encrypted, and in a further preferred feature is effected in accordance with a preceding, individualizing keying agreement.